One such cable duct is known from utility model DE 200 09 530. The cable duct shown therein serves, for example, to guide electrical conductors in an oil sealed manner from the interior of a motor or drive housing to the outside. The illustrated cable duct includes a duct body, designed to close an opening in the motor or drive housing, wherein the inner side of the duct body is exposed to oil. In the duct body is formed at least one cable channel connecting its inner and outer sides, through which channel an electrical conductor is guided, whose outer insulation over a portion of the length of the cable channel is replaced by a hardened plastic sealing material. The plastic sealing material is supposed to prevent oil from escaping through the cable channel from the inner side of the duct body to the outer side.
It has, however, been shown that the cable duct described in the above mentioned publication is not entirely oil tight. For one thing, hot and therefore very thinly fluid oil can penetrate by capillary effect into the interior of the stranded conductor and can move through the cable channel in the conductor interior. For another thing, the sealing mass as a result of an aging process tends to shrink so that a gap can form between the conductor and the sealing material or between the sealing material and the cable channel wall, through which gap the oil likewise can move from the inner side of the duct body to the outer side.